Max used inputs: 2 / still shows as a input !

I am trying to remove a sidechain input on a fx which was Max used inputs :4

I changed it to Max used inputs :2 , however it still shows a available sidechain input in platinum ?

Any one know why ?

I have tried doing a vst scan after changing the max input to 2, but after the scan it reverts it back to 4!

There has to be a way for this to work ?